CN1482375A

CN1482375A - Drum brake

Info

Publication number: CN1482375A
Application number: CNA031535453A
Authority: CN
Inventors: 右田五郎; 夫; 幸田秀夫; 堀贞彦
Original assignee: Yamaha Motor Co Ltd
Current assignee: Yamaha Motor Co Ltd
Priority date: 2002-08-16
Filing date: 2003-08-15
Publication date: 2004-03-17
Anticipated expiration: 2023-08-15
Also published as: JP4000025B2; EP1389695A3; TWI228472B; TW200415065A; CN100453841C; JP2004076840A; KR20040016391A; EP1389695A2

Abstract

Provided is a drum brake for a vehicle in which a support section for supporting one end each of brake shoes of a drum brake has a simple construction. A drum brake (3) for a vehicle configured such that one end each of a pair of brake shoes (15A, 15B) adapted to be in frictional engagement with the inside circumferential surface of a brake drum (13) provided in a rotary member (9) is supported by a fixed member (17) provided inside said brake drum (13), wherein a support portion (17A) of said pair of brake shoes (15A, 15B) to said fixed member (17) is formed in a convex shape and the support portion (17A) of said fixed member (17) corresponding to said pair of brake shoes (15A, 15B) is formed in a concave shape to be fitted for rotation to said convex shaped section.

Description

Drum brake

Technical field

The present invention relates to a kind of vehicle drum brake, this vehicle has brake drum that is arranged on rotating member and the brake shoe that is arranged in the brake drum.

Background technique

Fig. 8 is the expression overall structure of traditional drum brake 100 and the sectional view of parts around it.

Tradition drum brake 100 for example is used to make, and the trailing wheel RW1 of two-wheel vehicle stops the rotation.

Be supported on respect to the trailing wheel RW1 of postbrachium 102 rotation on the rear end of the postbrachium 102 that extends back from the body frame of two-wheel vehicle, the rear wheel drive mechanism 104 (for example driving mechanism) that rotation drives trailing wheel RW1 is arranged in the rear end of postbrachium 102.

That is to say, intermediate portion with respect to the running shaft member 106 of postbrachium 102 rotation is supported on the rear end of postbrachium 102, the base part of running shaft member 106 and 104 interlockings of rear wheel drive mechanism, rotating member 108 integrally is fixed on the front end of running shaft member 106.

For example, rotating member 108 is made of the wheel supporting member 112 on the cylindricality intermediate member 110 of a front end that is fixed on running shaft member 106 and the external peripheral surface that integrally is fixed on the intermediate member 110 that supports trailing wheel RW1.

Rotating member 108 forms the cylindricality brake drum 114 of the hollow that constitutes drum brake 100.The axis of the cylindricality brake drum 114 of the axis of running shaft member 106 and hollow overlaps basically.

In drum brake 100, a pair of semicircle brake shoe 116A, 116B are set around the rotating center at brake drum 114 (rotating center of running shaft member 106) in the brake drum 114 of rotating member 108 rotations.

Equally, the end of brake shoe 116A, 116B that each is relative engages with fixed component 122 on being arranged on fixed component 118, and the oval cam part 120B of cam 120 is set between the other end of brake shoe 116A, 116B, cam 120 is supported on rotation on the fixed component 118.

Further, the rotation of cam 120 makes the other end of brake shoe 116A, 116B engage with brake shoe 116A, 116B with the cam portion 120B of cam 120 and trails, thereby the brake lining that is arranged on the external peripheral surface of brake shoe 116A, 116B frictionally engages with inner circumferential surface at brake drum 114.

Described frictional engagement makes the trailing wheel RW1 of rotation stop or reducing rotating speed.

Cam 120 and fixed component 122 one of formation are roughly cylindricality and roughly are provided with respect to rotating member 106 with being mutually symmetrical, and their axis is that the axis that is parallel to rotating member 106 is arranged.

Fixed component 122 can form with the member that fixed component 118 separates by one.Equally, fixed component 122 is provided with one at the axis intermediate portion and has the flange portion 122B of big outer diameter and the pedestal end face on axial direction is provided with the outer diameter cylindrical section 122A littler than flange portion 122B.

Cylindrical section 122A is installed in the through hole on fixed component 118, further, for example on the end face of the fixed component on the pedestal end face 122, form the outside thread be used for installing nut N T1, fixed component 122 is fixed on the fixed component 118 by making between flange portion 122B that fixed component remains on and the nut N T1.

On the front-end face of fixed component 122, be formed for the cylindricality anastomosis part 122C that closes with the termination of each brake shoe 116A, 116B, an outer diameter be set on the axis centre of anastomosis part 122C keep body groove 122D less than the cylindricality brake shoe of bound fraction 122C.It is a groove that keeps brake shoe 116A, 116B that brake shoe keeps body groove 122D, thereby an end that can prevent each brake shoe 116A, 116B moves along the axial direction of fixed component 122.

Form the brake shoe 116A that engages with the anastomosis part 122C of fixed component 122, the bound fraction of 116B with the semicolumn spill, thereby they contact with anastomosis part 122C face, and further, on the thickness direction of the intermediate portion of the bound fraction of brake shoe 116A, 116B, projection 116C, the 116D that engages with brake shoe maintenance body groove 112D is set.

Cam 120 is cylindricality haply; Its front-end face is provided with the cam portion 120B with oval cross section, and it engages with fixed component 118 with rotation at the axis intermediate portion; It integrally is provided with swingle 124 on pedestal end face (being provided with the face of rear wheel drive mechanism 104).

By on its pedestal and with through hole that the pedestal termination on the cam 120 is closed swingle 124 integrally being fixed on the cam 120.

Outer diameter is arranged on the pedestal end face of cam 120 greater than the flange portion 120A of the inner diameter of the conjugate foramen on the fixed component 118, and adjacent with the cam portion 120B that forms on the front-end face of cam 120.

When cam 120 is installed on the fixed component 118, with the pedestal end of cam 102 is the place ahead with cam 102 from the face that is provided with brake shoe 116A, 116B is inserted in conjugate foramen on the fixed component 118, lean up to flange portion 120A and fixed component 118, thereby swingle 124 is connected on the pedestal end of cam 120.

The pedestal end of the swingle 124 that engages with cam 120 is thicker on the axial direction of cam 120.

That is to say, the pedestal end of swingle 124 by a plate portion 124A with on its thickness direction, can constitute from another plate portion 124B that discoid plate 124A separates, these plate portions 124A, 124B are being provided with corresponding through hole on the thickness direction and on the same axis, through hole combines with the pedestal end of cam 120.

It is that swingle 124 is stablized, is securely fixed on the cam 120 that the pedestal end of swingle 124 forms thicker reason.For example, at the inner diameter of the through hole that forms on the pedestal end of swingle 124 slightly greater than the outer diameter on the pedestal end at cam 120, thereby can farthest reduce the swing (in the direction of arrow A R81) that on the front-end face of swingle 124, produces.

The front end of swingle 124 engages with the center line of wirerope 126, and the axial displacement of center line makes swingle 124 rotations of rotating cam 120.The rotation of cam 120 trails cam portion 120B rotation and brake shoe 116A, the 116B of cam 120, thereby makes drum brake 100 work.

In described traditional drum brake 100,, thereby make the supporting structure of brake shoe 116A, 116B in drum brake 100 complicated because fixed component is arranged on the fixed component 118 supporting the end of each brake shoe 116A, 116B.

In addition, the pedestal end of cam 120 stretches to rear wheel drive mechanism 104 from the side 118A of fixed component 118 (being provided with the side of rear wheel drive mechanism 104), be installed on the outstanding cylindrical section at the through hole on the pedestal end of swingle 124, thereby swingle 124 is fixed on the pedestal end of cam 120.

Therefore, in order to make swingle 124 be connected the pedestal end of cam 120, cam 120 is installed under the state on the fixed component 118, the end face of the pedestal end of cam 120 and be greater than thickness at the swingle 124 of pedestal end (distance between the outer surface of the outer surface of plate portion 124A and plate portion 124B) at the distance D M1 between the 102A of the side of the postbrachium on the face of fixed component 118 102.

If big distance D M1 determined, become big at trailing wheel RW1 or drum brake 100 and the distance that is equipped with between the postbrachium 102 of rear wheel drive mechanism 104, cause becoming big at width or the transverse dimension of the trailing wheel RW1 of two-wheel vehicle.

Described problem is not only at the trailing wheel that is present in two-wheel vehicle but also be present on other wheels of two-wheel vehicle.

From described angle, an object of the present invention is to provide a kind of for motor vehicle drum brake, the supporting part that wherein supports an end of each brake shoe in the drum brake has simple structure.

Equally, an object of the present invention is to provide a kind of for motor vehicle drum brake, width or transverse dimension that the wheel of drum brake wherein is housed can be reduced to minimum degree.

Summary of the invention

Technological scheme 1 of the present invention provides a kind of automobile-used drum brake with following structure, promptly, the end of each is supported by the fixed component that is arranged in the described brake drum in a pair of brake shoe, this brake shoe frictionally engages with the inner circumferential surface of brake drum in being arranged on rotating member, wherein forms convex and forms spill to be suitable for described convex partial rotation corresponding to the supporting part of the described fixed component of described a pair of brake shoe corresponding to the supporting part of the described a pair of brake shoe of described fixed component.

Claim 2 of the present invention provides a kind of automobile-used drum brake with following structure, promptly, the end of each is supported by the fixed component that is arranged in the described brake drum in a pair of brake shoe, one end of this brake shoe frictionally engages with the inner circumferential surface of brake drum in being arranged on rotating member, wherein, supporting part corresponding to the described a pair of brake shoe of described fixed component forms spill, forms convex to be suitable for described concave portions rotation corresponding to the supporting part on the described fixed component of described a pair of brake shoe.

Claim 3 of the present invention provides a kind of automobile-used drum brake with following structure, promptly, one end of a pair of brake shoe is supported by the fixed component that is arranged on the fixed component in the described brake drum or be arranged on the fixed component, one end of this brake shoe frictionally engages with the inner circumferential surface of brake drum in being arranged on rotating member, the cam that is used for the other end of the described brake shoe of opening/closing is arranged on the described fixed component and rotates, wherein, the swingle of described cam rotation integrally is arranged on the described cam, described swingle and the working beam that is arranged on the end that makes the jack shaft of operating described working beam are in the same plane basically, and the front end of described swingle links to each other by a rod hinge connection ground with the front end of described working beam.

Claim 4 of the present invention provides automobile-used drum brake as claimed in claim 2, and wherein, described swingle has and is supported on the shaft portion that rotates on the described fixed component, and described cam integrally is arranged on the described shaft portion of described swingle.

Description of drawings

Fig. 1 is that the integrally-built view according to the two-wheel vehicle of the drum brake of the embodiment of the invention is equipped with in expression.

Fig. 2 is the drum brake sectional view of the cross section IIA-IIB in the presentation graphs 1.

Fig. 3 is the sectional view of the cross section IIIA-IIIB in the presentation graphs 2.

Fig. 4 is the sectional view of the cross section IVA-IVB in the presentation graphs 3.

Fig. 5 is the view that is illustrated in the wirerope part of extreme lower position.

Fig. 6 is second view that is illustrated in the wirerope part of extreme lower position.

Fig. 7 is the three-view diagram that is illustrated in the wirerope part of extreme lower position.

Fig. 8 is traditional drum brake of expression and the sectional view of peripheral part thereof.

Embodiment

Fig. 1 is a kind of integrally-built view of the two-wheel vehicle 1 of drum brake 3 according to an embodiment of the invention that is equipped with.

Two-wheel vehicle 1 is that a kind of motor drive mechanism EM1 by rotation drives the vehicle that trailing wheel RW1 travels and comprises the main frame MF1 of the car body that constitutes two-wheel vehicle 1; Support by the front end of main frame MF1 with respect to the handle HD1 of main frame MF1 rotation, below handle HD1 support by front-wheel FW1 with respect to handle HD1 rotation.

The rear end is provided with on main frame MF1: the driver of a two-wheel vehicle 1 takes and is subjected to from the below vehicle seat SD1 of the support of main frame MF1, a power supply or a battery BR1 for the motor drive mechanism EM1 supply electric energy of rotation.

The swing of postbrachium 5 is supported by the following rear end of main frame MF1, and the rotation of trailing wheel RW1 is supported on the rear end of postbrachium 5.

The end of posterior bumper RC1 can swingingly be supported on the longitudinal middle part (direction from front to back of two-wheel vehicle 1) and its upper side of postbrachium 5, and the other end of posterior bumper RC1 can swingingly be supported on the main frame MF1 of below of seat SD1.

Master bracket MS1 is arranged on the bottom of two-wheel vehicle 1 and its longitudinally on the middle part, and this master bracket makes two-wheel vehicle 1 roughly be in the position of level in the horizontal when two-wheel vehicle 1 is parked.

When two-wheel vehicle 1 began to travel or quickens, the EM1 of rotary electric mechanism was as motor; When two-wheel vehicle 1 slowed down, it was as the generator that the kinetic energy of vehicle 1 is changed into electric energy.As the EM1 of rotary electric mechanism during as generator, the power storage that is produced by the EM1 of rotary electric mechanism is in battery BR1.

Now, drum brake 3 is described.

Fig. 2 is the viewgraph of cross-section of the drum brake 3 of cross section IIA-IIBD in the presentation graphs 1,

Fig. 3 is the view of the cross section IIIA-IIIB in the presentation graphs 2, and Fig. 4 is the view of the cross section IVA-IVB of presentation graphs 3.

Omitted the diagrammatic sketch of rotating member 9 and brake disks 13 at Fig. 3.

In drum brake 3, on the fixed component (fixing member) 17 of drum brake part 3, be used to support each brake shoe 15A, the supporting part 17A of the end of 15B and at each brake shoe 15A, the structure of the counterpart of the structure of the supporting part that the end of 15B will engage with supporting part 17A and traditional drum brake 100 is different, simultaneously, in drum brake 3, with the anastomosis part of the fixed component 17 of drum brake 3 and cam 19 and make the swingle 21 of the cam 19 rotations mechanism relevant be different from respective members and mechanism in traditional drum brake 100 with similar component, yet aspect other, the layout of drum brake 3 is roughly identical with traditional drum brake 100.

That is to say, the structure of drum brake 3 is as follows: the end of each supports by constituting the supporting part 17A that is arranged on fixed component 17 parts in the brake drum 13 among a pair of brake shoe 15A, the 15B, and it frictionally contacts with the inner circumferential surface of brake drum 13 in being arranged on rotating member 9.

Each all forms convex corresponding to supporting part 15C, the 15D of a pair of brake shoe 15A, the 15B of support fixation member 17, all forms spill so that be suitable for the rotation of convex part (see figure 3) corresponding to the supporting part 17A part of the fixed component 17 of a pair of

brake shoe

15A, 15B.

Each supporting

part

15C, 15D among a pair of brake shoe 15A, the 15B form spill, form convex to be suitable for the rotation of concave portions corresponding to the part of each supporting part on the fixed component 15 of a pair of

brake shoe

15A, 15B.

That is to say, also can a pair of brake shoe each all forms spill and each all forms convex so that be suitable for the concave portions rotation corresponding to the part of the supporting part of the fixed component of a pair of brake shoe corresponding to the supporting part of support fixation member 17.

Further, in Fig. 3, have only the supporting part 15C of brake shoe 15A to form spill and have only the supporting part formation convex of the fixed component 17 that the supporting part of fixed component 17 engages with the supporting part 15C of brake shoe 15A.

Equally, in Fig. 3, the cam 19 that is used for the other end of opening/closing

brake shoe

15A, 15B is arranged on the fixed component with rotation.

Equally, the swingle 21 of cam 19 rotations integrally is arranged on the cam 19; Swingle 21 and the working beam 23 that is arranged on the end of the intermediate bar 25 that makes working beam 23 work are in a plane basically; The front end of the front end of swingle 21 and working beam 23 is hingedly connected together by a connecting rod 26.

Equally, swingle 21 has is supported on the fixed component 17 with the shaft portion 21A of rotation, and cam 19 integrally is arranged on the shaft portion 21A of swingle 21.

Now, will to drum brake 3 and around it parts describe in detail.

Be supported on the rear end of the postbrachium 5 that extends back from the body frame MF1 of two-wheel vehicle 1 driving mechanism TM1 and be arranged in the rear end part of postbrachium 5 by the EM1 of rotary electric mechanism that driving mechanism TM1 drives trailing wheel RW1 rotatably with respect to the trailing wheel RW1 of postbrachium 5 rotation.

Be supported on the rear end of postbrachium 5 with respect to the intermediate portion of the rotating shaft member 7 of arm 5 (fixed component 17) rotation, the pedestal end of running shaft member 7 and driving mechanism TM1 interlocking, rotating member 9 is fixed on the front end of running shaft member 7, and this rotating member supports the wheel supporting member 11 that is used for supporting trailing wheel RW1.

Equally, rotating member 9 has formed the cylindrical brake drum 13 that constitutes the hollow of drum brake 3.The axis centre of the cylindrical brake drum 13 of the axis centre of running shaft member 7 and hollow overlaps basically.

Equally, in drum break 3, a couple half

garden brake shoe

15A, 15B around for example traditional bulging break 100, the rotation centerline of brake drum 13 (rotating center of running shaft member 7) are arranged in the brake drum 13.

Equally, the end of

brake shoe

15A, 15B that each is relative engages with the supporting part 17A of fixed component, and is provided with the oval cam part 19B of cam 19 between the other end of each

brake shoe

15A, 15B, and cam 19 is supported by fixed component 17 and rotates.

Further, the rotation of cam 19 makes the other end of

brake shoe

15A, 15B engage and make

brake shoe

15A, 15B to trail with the cam portion 19B of cam 19, thereby is arranged on brake lining (not shown) on the external peripheral surface of

brake shoe

15A, 15B and the inner circumferential surface of brake drum 13 takes place by engaging of friction.

The joint of described friction makes rotation trailing wheel RW1 stop or reducing its rotational speed.

The main body of supporting part 17A and fixed component 17 is formed by a single member.For example, can be used as the fixed component 17 that a member casts out the part with corresponding supporting part 17A, by processing cast construction is shaped then, therefore on fixed component 17, form supporting part 17A.

On supporting part 17A, form a pair of termination merging and have recessed arc anastomosis part with each brake shoe 15A, 15B.Pair of engaging part forms symmetrically with respect to the straight line at the center of spin axis that connects running shaft member 7 and supporting part 17A (see figure 3) basically, further, has identical thickness on the axial direction of running shaft member 7 (see figure 4)s.

Correspondingly form anastomosis

part

15C, 15D on the end of each

brake shoe

15A, 15B, the contact that push this anastomosis part and the anastomosis part of corresponding supporting part 17A also forms protruding arc.

Equally, as shown in Figure 4, in order to prevent that

brake shoe

15A, 15B from skidding off from fixed component 17 on the axial direction of running shaft member 7, on the front end as the supporting bead WS1 of the supporting element of an end that supports each

brake shoe

15A, 15B and the supporting part 17A (from the opposing side of the EM1 of rotary electric mechanism) that bolt B T1 is fixed on member 17.

Projection 19 and supporting part 17A are arranged on respect on the symmetrical haply position of running shaft member 7, and the thickness direction of the axial direction of cam 19, the anastomosis part of supporting part is parallel with the axis centre of running shaft member 7 with the axial direction of

brake shoe

15B, 15C (thickness direction).

Cam 19 forms tubular haply.On the front end of cam 19, form the cam portion 19B have oval cross section and engage, be installed on the shaft portion 21A of swingle 21 at the pedestal end of the cam 19 of axial direction and be fixed in the above with the other end of

brake shoe

15A, 15B.

That is to say that the shaft portion 21A of swingle 21 forms cylindrical, be bonded together by its inner circumferential surface and a through hole that is arranged on the fixed component 17 and rotate, and its inside of cylindrical base partial fixing of cam 19.

Cam 19 and swingle 21 are to arrange around the axis of the rotating center that is parallel to running shaft member 7 with respect to fixed component 17.

One end of connecting rod (connecting rod) 26 (rotatable) pivotally is connected with the front end of the bar of swingle 21 part, and the other end of connecting rod 26 hingedly is connected on the front end of working beam 23.

The pedestal end of working beam 23 integrally is arranged on the pedestal end of jack shaft 25; Support jack shaft 25 rotations by be supported on its pedestal end and intermediate portion at postbrachium 5 and fixed component 17 making, the front end of jack shaft 25 stretches out from postbrachium 5; The pedestal end of swingle 29 is fixed on the extension; Wirerope 27 is arranged on the front end of swingle 29, as on the swingle 124 on traditional drum brake 100.

The rotating center of jack shaft 25 is arranged essentially parallel to the rotating center of running shaft member 7, and is fixed at the fixed component 17 of the rear end of postbrachium 5 on the side of postbrachium 5 (being provided with the side of

brake shoe

15A, 15B and the trailing wheel RW1 of drum brake 3).That is to say that fixed component 17 and postbrachium 5 have together constituted the rear end of postbrachium 5, further, the lateral opening on the rear end of postbrachium 5 is closed by fixed component 17, thereby the space of the EM1 of rotary electric mechanism and similar space are arranged in the rear end of postbrachium 5.

Working beam 23, swingle 21 (the bar part of swingle 21) and connecting rod 26 are arranged on same plane basically.Equally, working beam 23, swingle 21 (the bar part of swingle 21) and connecting rod 26 is arranged in the postbrachium 5 and in the narrow space between EM1 of rotary electric mechanism and fixed component 17.

When drum brake 3 is assemblied in the postbrachium 5, the fixed component that has

brake shoe

15A, 15B 17 that assembles in advance, cam 19, swingle 21, connecting rod 26, this postbrachium fixed component 17 of working beam 23 and jack shaft 25 is fixedly mounted on the postbrachium 5.

When the swingle 29 of drum brake 3 when initial position rotates,

brake shoe

15A, 15B are rotatable from brake disc 13 disengagings and rotating member 9 on this initial position, thereby jack shaft 25 rotations make cam 19 rotations by the connecting rod 26 and the swingle 21 of working beam 23 and formation linkage mechanism, the cam portion 19B of cam 19

trails brake shoe

15A, 15B, the brake lining (not shown) that is arranged on brake shoe 15A, the 15B frictionally contacts with the inner circumferential surface of brake drum 13, and this brake lining has limited the rotation of rotating member 9 and trailing wheel RW1.

In drum brake 3, by form as single member as the main body of fixed component 17 supporting part 17A support the rotation of the end of each

brake shoe

15A, 15B, thereby fixed component does not need to be provided with the additional fixed component in the picture transmission system, has so just simplified the structure of supporting part of an end of each

brake shoe

15A, 15B of support drum brake 3.

The fixed component 122 of tradition drum brake 100 is provided with flange portion 122B, brake shoe keeps the male thread portion on groove 122D and the pedestal end, and this male thread portion has increased the manufacture cost of fixed component 122.Native system need not fixed component 122, thereby can reduce the manufacture cost of drum brake 3 widely.

Equally, in drum brake 3, the swingle 21 of rotating cam 19 integrally is arranged on the cam 19; Working beam 23 on one end of swingle 21 and the jack shaft 25 that is arranged on operation element bar 23 is provided with at grade (axis that is substantially perpendicular to trailing wheel and running shaft member 7) basically, the front end of the front end of swingle 21 and working beam 23 is by the connecting rod 26 formation linkage mechanism that pivotally is connected, further, arrange that linkage mechanism at grade is provided with in the narrow space between fixed component 17 and the EW1 of rotary electric mechanism (axial width of trailing wheel RW1 is narrow), thereby can farthest reduce the trailing wheel RW1 that is provided with drum brake 3 width and horizontal (axially) size on every side on the two-wheel vehicle 1.

That is to say, compare, can make the more close drum brake 3 of the EM1 of rotary electric mechanism that is provided with the spin axis coaxial line ground of trailing wheel RW1 with legacy system.

Further, in two-wheel vehicle 1, the EM1 of rotary electric mechanism constitutes the mini engine in the rear end that is arranged on postbrachium 5, for example axially having little axial clearance motor as the EM1 of rotary electric mechanism on (axially very narrow), thereby can reduce to be equipped with width or horizontal (axially) size around the trailing wheel RW1 of two-wheel vehicle 1 of drum brake 3 further.

As a result, compare with legacy system, the center of the more close trailing wheel RW1 of trailing wheel RW1 center of gravity in the horizontal of two-wheel vehicle 1, thus improved the lateral stability of two-wheel vehicle 1.Equally, can reduce to minimum degree to the size of overhang on the direction that the EM1 of rotary electric mechanism is set of the trailing wheel RW1 of two-wheel vehicle.

Further, in brake drum 3, swingle 21 is provided with the shaft portion 21A that is supported on rotation on the fixed component 17, cam 19 integrally is arranged on the inner circumferential surface of shaft portion 21A of swingle 21, thereby the outstanding size with the swingle 21 that stretches out from fixed component 17 is the same, also can reduce swingle 21 and cam 19 size in the axial direction.Thereby, reduced the axial dimension of drum brake 3.

Further, in brake drum 3, need not the required fixed component of tradition, that is to say, can make one of the decreased number of the parts that constitute drum brake 3, thereby the accumulated error of the drum brake 3 that the assembling back is caused by the foozle of the parts of drum brake 3 reduces to minimum degree.

In drum brake 3, for example wirerope replacement working beam 23, connecting rod 26 and swingle 21 make cam 19 rotations can to use a power transmission members.

In addition, drum brake 3 also be useful in two-wheel vehicle by on the oil-engine driven trailing wheel, also can be used on except that trailing wheel wheel or except that two-wheel vehicle on the wheel of vehicle.

Now, will be to being described (see figure 1) at the wirerope 27 that moves from handle HD1 to trailing wheel RW1 with the drum brake 3 on the trailing wheel RW1 that drives two-wheel vehicle 1.

Fig. 5 to 7 is views that expression is arranged on the extreme lower position of the wirerope 27 on the two-wheel vehicle 1; Fig. 5 is the view that arrow VA-VB place intercepts in Fig. 1; Fig. 6 is the view that the arrow VIA-VIB place in Fig. 5 intercepts; Fig. 7 is the view of the cross section of the wirerope 27 in the expression axially.

In two-wheel vehicle 1, the jack shaft 25 of drum brake 3 is arranged on the upside of the postbrachium 5 of car rear end.Swingle 29 (see figure 1)s are arranged on the front end of jack shaft 25.The pedestal end of aforesaid swingle 29 is fixed on the jack shaft 25, and wirerope 27 is connected on the front end of swingle 29.

The brake rod that wirerope 27 is used from the rear wheel brake on the handle HD1 that is arranged on two-wheel vehicle 1 moves to swingle 29, and it is through in trailing wheel brake rod and the position below the working beam 29 in the middle part of the body frame MF1 of two-wheel vehicle 1 (see figure 1) haply.

Wirerope 27 as shown in Figure 7 by elongated

tubular cover member

27B, 27C and one be arranged among sleeve part 27B, the 27C can longitudinal movement and transmit the long center line 27A of mechanical operation signal according to center line 27A with respect to the displacement amount of

cover member

27B, 27C.

First portion from the two-wheel vehicle of a trailing wheel brake rod that handle HD1 is housed on the extreme lower position of wirerope 27 moves to a second portion that the non-first portion of drum brake 3 is housed, and always be in the below of first and second parts, be provided with a through hole 31 below

sleeve part

27B, 27C, water is discharged (see figure 7) by the gap that this hole enters between center line 27A and

cover member

27B, 27C.

Now, wirerope 27 and through hole 31 are described in detail.

Shown in Fig. 5,6, make the wirerope 27 that is arranged on the two-wheel vehicle 1 be fixed on its minimum point on the pedal supporting element that the lower space of body frame MF1 is installed by the support BK1 on the external peripheral surface that is arranged on cylindricality connector element 27D.

Equally, as shown in Figure 7, the center line 27A of wirerope 27 is by covering at cover member 27B between the trailing wheel brake rod of connector element 27D and handle HD1 and the cover member 27C between the swingle 29 of connector element 27D and drum brake 3.

Equally, be arranged on two of connector element 27D vertically ends with the outer peripheral surface engaging hole engaged of the end of cover member 27B and another outer peripheral surface engaging hole engaged, end of each

cover member

27B, 27C and connector element 27D two vertical the engaging to make and overlap

member

27B, 27C and be fixed on the connector element 27D of end with the end of cover member 27C.

A through hole that is used for passing center line 27A is set, two conjugate foramen coaxial lines of vertically holding of this through hole and connector element 27D on vertical intermediate portion of connector element 27D.

A through hole 31 is set on vertical intermediate portion of connector element 27D to be connected to the through hole at aforesaid vertical intermediate portion on the outside of connector element 27D.The pedal supporting member PB1 that is fixed on body frame MF1 as connector element 27D goes up so that the water in connector element 27D is discharged to the outside, and when it was arranged on the extreme lower position of wirerope 27, through hole 31 passed connector element 27D and is provided with from connector element 27 (gap between center line 27A and connector element 27D) inside downwards along two-wheel vehicle.

In wirerope 27, through hole 31 is arranged on the extreme lower position of wirerope 27, this through hole links to each other the gap between the center line 27A of

cover member

27B, 27C, connector element 27D and wirerope 27 with outside at wirerope 27, thereby can be discharged to the outside of wirerope 27 at an easy rate by through hole 31 from the water that an end of wirerope 27 enters the gap.

Like this, the water in wirerope 27 can be discharged at an easy rate, thereby the center line 27A that can prevent wirerope 27 gets rusty.

According to claim 1 of the present invention or 2, for motor vehicle drum brake is arranged so that the supporting part of brake shoe one end that supports each drum brake has simple structure.

According to claim 3 of the present invention or 4, the drum brake that wheel is used can be arranged so that width or the transverse dimension around the wheel that is equipped with drum brake is reduced to minimum degree.

Claims

1. a for motor vehicle drum brake has following structure: an end of a pair of brake shoe that frictionally engages with the inner circumferential surface of brake drum on the rotating member is supported by the fixed component that is arranged in the described brake drum, described for motor vehicle drum brake, it is characterized by

Each supporting part corresponding to the described a pair of brake shoe of described fixed component forms convex, forms spill to be suitable for described convex partial rotation corresponding to the supporting part of the described fixed component of described a pair of brake shoe.

2. a for motor vehicle drum brake has following structure: an end of a pair of brake shoe that frictionally engages with the inner circumferential surface of brake drum in being arranged on rotating member is supported by the fixed component that is arranged in the described brake drum, described vehicle drum brake, it is characterized by

Supporting part corresponding to the described a pair of brake shoe of described fixed component forms spill, forms convex to be suitable for described concave portions rotation corresponding to the supporting part on the described fixed component of described a pair of brake shoe.

3. for motor vehicle drum brake has following structure, promptly, one end of a pair of brake shoe that frictionally engages with the inner circumferential surface of brake drum in being arranged on rotating member is supported by the fixed component that is arranged on the fixed component in the described brake drum or is arranged on fixed component, the cam that is used for the described brake shoe the other end of opening/closing is arranged on the described fixed component with rotation, described vehicle drum brake, it is characterized by

The swingle of described cam rotation integrally is arranged on the described cam, described swingle and be arranged on that working beam is in same plane basically on the end of the jack shaft that makes described working beam work, the front end of described swingle is connected by a rod hinge connection ground with the front end of described working beam.

4. for motor vehicle drum brake as claimed in claim 2, wherein said swingle have the shaft portion that is supported on the described fixed component with rotation, and described cam integrally is arranged on the described shaft portion of described swingle.